Learn about Solid Tools in Google SketchUp 8.
With the SketchUp Intersect Faces tool, you can achieve many of the same things that the Solid Tools do. Intersect Faces takes longer because it requires an awful lot of cleanup; however, it’s still useful for two very important reasons: It’s available in both the free and Pro versions of SketchUp, and it works on any face in your model — not just on solids.
TIP
You might find the easiest way to use the Solid Tools is to preselect the solids you want to use and then choose the tool to carry out the operation. The glaring exceptions to this rule are the Subtract and Trim tools; both of these depend heavily on the order in which you pick your solids. Take a peek at the table for more specifics.
